discharge during pregnancy and irritation??? (long post)

Ive always had a natural discharge all of my life that has been normal so im not new to having to wear pantiliners everyday, but this is insane!!! The discharge i have now is the same color as before but there is so much more that it is causing irritation to my skin (down there). At first i thought i had a yeast infection so i called the doc, explained what was going on and she prescribed me medication for it. BUT THAT DIDNT WORK!!! Im not itching internally AT ALL. The skin externally is very irritated and it itches horribly!! ive been using so much gold bond medicated powder i could lose my mind!!! Anyone else having this problem or any suggestion to get rid of the irritation?